Improvement in sectional coffer-dams



UNrrEn vSTATE-s PATENT OFFICE..

lHOMAS BRACHER, OF RAHLAY, NEW' JERSEY.

Specification forming part ,of Letters Patent No. 95,976, dated October 19, 1809.

'To @ZZ whom it may concern.-

Beit known that I, THOMAS BRAcHER, of Rahway, in the county of Union and State of New Jersey, have invented a new and useful vImprovement in Cotter-Dams; and I do heres,

b v declare the following to be-a'full, clear", and exact description of the construction and operation of the same, reference being had to the accompanying drawings,l in which- Figure l is a View of one of the sections of which the dani is composed, and Fig. 2 a top view illustrating the manner in which the sections are united with each other.

Similar letters of reference indicate like parts in the several drawings. p

My invention consists inthe employment and use of a series of curved metal plates, riv- ,eted together, and .so arranged in sections that they may be interlocked together in any desired position, as will be fully setA forth hereinafter.

To enable others skilled inthe art to make and use my invention, I will describe the construction and operation of the same.

The sections of which the coiffer-dam isbnilt,

l the opposite sections, when several sections are provided with a series of catches, C, at one end, and a projection onbar, a, secured tothe other. In using these sect-ions to form a dam they are placed one at a time in position in the stream, each section being lowered separately into place,` and piles are then drivendown in front of the bars B, to which ropes are tied and secured to anchors placed at adistance in the stream, in order to keep the sections in an upright position against the pressure of 'the water on the outer convex sides of the sections. The' joints are calked by driving Wedges between the catches and the ends of the sections, ,to press them together, or any other mode may be employed to eii'ect the same object; When the dam is completed, theinclosed water is removed by pumping.

Having thus fully described my invention, I clamv A sectional coffer-dam constructed of a series of curved sections formed of metal plates A,rivetcd together and to cross-bars B, and

G. A. DURGIN, EDWARD'E. OsBoRN..

joined together. Each section is therefore provided with interlocking devices, wherebyl 

